A triangle has sides with lengths: 3, 8, and 19. How do you find the area of the triangle using Heron's formula?
This is not valid lengths for three sides of any triangle.
The area can not be calculated.
For any triangle the longest side must be less than the sum of the two shorter sides.
If you attempted to use Heron's formula you would find that you needed to evaluate the square root of a negative value: